Genotype 1 Most Prevalent Worldwide

Messina JP. Hepatology. 2014;doi:10.1002/hep.27259. 

Hepatitis C virus genotype 1 is the most prevalent genotype and accounts for 83.4 million infections, or 46.2% of all cases, worldwide, according to a study published in Hepatology.

Researchers reviewed 1,217 studies published from 1989 to 2013 in an effort to compile a large survey of global HCV genotype prevalence. They tabulated HCV cases for each genotype in 117 countries, with data that encompassed 90% of the world population. Those data were combined with estimates of overall HCV prevalence based on the WHO Global Burden of Disease regions.

Source: Messina JP

“Understanding the global trends in the genetic makeup of HCV is the focus of our study and imperative in developing new treatment strategies that may save millions of lives around the world,” Jane P. Messina, PhD, from the department of zoology at University of Oxford, said in a press release.

According to the results, genotype 1 accounted for almost half of HCV cases in the world, with more than one-third of cases reported in East Asia. Genotype 3 was the second most common (30.1%), with about 75% of cases reported in South Asia. Next was genotype 2 (9.1%), which is reported primarily in East Asia; 4 (8.3%), reported primarily in North Africa; and 6 (5.4%), reported primarily in East Asia. Genotype 5 accounted for less than 1% of cases worldwide, with the majority reported in Southern and Eastern sub-Saharan Africa.

Sixty-six percent of genotype 1 cases were reported in countries classified by WHO as high-income, whereas genotypes 4 (18.5%) and 5 (5.9%) were more common in countries classified as low-income.

“Although genotype 1 is most common worldwide, non-genotype 1 HCV cases — which are less well served by advances in vaccine and drug development — still comprise over half of all HCV cases,” the researchers concluded.

Disclosure: Messina reports receiving support from the European Union-funded IDAMS consortium.